This morning we find the big ocean storm intensifying rapidly as predicted. I think itís a good thing this storm is so far offshore, as had it come a hundred miles closer Iíd likely have no power and be stuck inside all day. The size of this storm is dangerous and while I love a good snowstorm, this one had the potential to do some real damage and bring southern New England to a standstill. But, the storm isn't close to us so it's really a non-event for almost everyone.
Across Cape Cod and the Islands the system is close enough to be bringing snow and wind and prompting blizzard warnings to be issued. A blizzard is issued when visibility is going to be less than one quarter mile for three hours or longer. The reason for the low visibility must from falling or blowing snow with winds of at least 35 miles per hour.
As of this morning, several towns across Cape Cod have reported blizzard continues and the warning remains until 2PM. The snow is not making it very far to the north and Boston may not see more than a few flurries. The highest snow totals are going to be over the southern elbow of the Cape perhaps even in Chatham itself.
Snow continues moderate to heavy especially along the immediate coastline and south shore of the area. I updated the snowfall map for metro Boston slightly. The largest totals will be south of Plymouth. There the heavy snow will create a situation where driving will become virtually impossible through about midnight. The heavy snow and wind will also impact the immediate shore line. Route 1 from Boston to Salem and through the North Shore will also continue very difficult this evening. The further west you are, the less difficult travel will be. For the most populated parts of eastern Massachusetts this is a small event while for parts of southeastern areas and Cape Cod, it's quite a different story.
Explosive cyclogeneis or bombogenesis are meteorological terms used to describe the rapid intensification of a low pressure system or storm. Atmospherically, the air is rushing off the planet so fast in the center of the storm it creates an air hole of sorts in the middle. Air then rushes in to replace the rapidly rising air and results in a lot of wind. Itís sort of like digging a hole at the beach and watching the water fill it up really fast. This is the weather situation we have developing right now. In these situations a tiny shift in the storms track and your position relative to the storm can have major implications to snow totals.
Picture yourself trying whack someone with your hand, Iíll let you choose who it is. If at the same time you extend your arm to impact them, you started moving away you might miss them. If you move quickly, you give them a glancing blow and if you slow down they feel the full impact of your hand. The big ocean storm is going to brush areas just west of Worcester while hitting areas over Cape Cod full force. Ok, enough analogies, I know get the accumulation.
Blizzard defined again
A blizzard is a three hour periods when winds blow at over 35 miles oer hour and the visibility (how far you can see ahead)is reduced to under one-quarter mile, due to either falling snow or snow blowing around off the ground. The weather service expects these conditions to be met along the coast so a blizzard warning has been issued.
When it begins
The storm hits this afternoon roughly between 2 and 4PM and then ramps up to full force between 6PM and midnight. During this time, the snow could come down at 1 to 3 inches per hour. While all this is happening, the back edge of the snow will already be pushing eastward.
I'll be updating the forecast throughout the weekend here and on Twitter @growingwisdom.
The further east you live, the longer it will snow and therefore the higher the amounts. There will likely be very sharp gradients of snow totals again from Rockport to Reading and Boston to Boxford.
The snow is going to get blow around a lot. Winds will be strong with the storm and there could again be scattered power outages from this quick hitting noríeaster. Much of Cape Cod has started as snow and without any rain I have increased totals similar to those on the other side of the canal through Plymouth.
What could change
From this point forward I will be watching the radar to see where the heaviest bands set up and who will likely have the most snow. Remember, there are ranges of snow totals because snow amounts vary wildly over a short distance.
When it ends
Between 1AM and 4AM the entire system pulls east, the snow ends and skies start to clear. Cold weather returns behind the system for two days. Highs Sunday and Monday only reach the 20s.
Tuesday night or Wednesday, we have the next storm with more snow or snow and rain, this looks to be light. Iíll have details over the weekend. It does turn milder after that and I promise highs reach at least the 40's by the end of the week.
The back edge of the snow continues to press eastward. The image below is as of 8:00AM and you can see much of eastern Massachusetts is still experiencing some accumulating snow. The snow is basically over, but there are still snow showers/light snow around. You will likely still see some snow in the air as late as 12PM in the city, but it won't be accumulating and the sun will be able to be seen through the clouds. I have noted the areas of heaviest snow bands on this radar image. Notice the green color, that's the indication of heavy snow on a this radar.
The storm has produced over two feet of snow across parts of Essex County where bands of ocean effect snow gave those areas a jump start of 10 or more inches before the main part of the storm even arrived. Logan Airport has seen just shy of 15 inches of new snow since this storm began. Boxford was one of the hardest hit areas with over 2 feet! The snow was caused by the identical meteorological phenomena that bring big snows to Buffalo and Watertown, New York. As the bitter air rushed over the ocean water it picked up moisture and dumped it on a narrow area of Essex County.
You will no doubt want to know when this is over. The accumulating snow will end first, then there will be snow in the air a bit longer, maybe an hour or two after that. You could even see some breaks of sunshine with some flakes still falling. The map below gives approximate times for the snow to end. Iíll be updating on Twitter @growingwisdom all morning as the back edge of the snow progresses eastward.
The cold is incredible. When I started blogging this morning it was 2 above in Boston, just three degrees shy of the January record for today. It's now a balmy 5. I donít use the words bitter, frigid, or dangerous very much when it comes to cold, but today they are all appropriate. This kind of cold and wind will impact not only people, but pets and even some plants. This spring, I suspect some winter damage to some of our gardens to be evident. Spring is 75 days away, so Iíll think more about it later.
If you are shoveling, snow blowing, be sure to take breaks. It will only take a short period of time for your skin to get frostbite. The chart below gives you an idea how quickly damage to your finger and nose could occur if you are outside. Wind chills this morning are in the 15-20 below range. This is Canada cold. Wind chills remain below zero all day, staying in the 5 to 15 below range until sunset.
There is one more high tide cycle for the coast and there will be minor or moderate coastal damage. The chart below shows which harbors are susceptible to the high tide. There hasnít been any structural damage thus far from the storm, but this next high tide could do some of that type of damage. That type of damage isnít going to be widespread if it did occur at all.
The cold relaxes tomorrow afternoons temperatures rise over 25 degrees. When you get up tomorrow, it will be below zero in most areas, including Boston. Milder air will push the arctic air away and I think you will be surprised how warm mid-20s feels after today and tomorrow morning.
Our next storm is a warmer one with rain. Temperatures by Sunday will reach well into the 30s to lower 40s and rain moves in by nightfall. The rain continues Monday with highs in the 40s, there will be significant melting, but not 2 feet of it for those of you with the super big accumulations.
Another cold blast returns for Tuesday, but not as cold as this one. Highs on Tuesday will be only in the single numbers to lower teens, certainly bitter again, but not quite as extreme as today.FULL ENTRY
The blizzard warning continues overnight for much of the Massachusetts coastline, but doesn't include the city of Boston. This warning extends all the way north to Rockland, Maine. Blizzard warnings mean visibility will lower to a quarter mile or less for 3 hours because of the strong winds which will blow the snow. The snow will be heavy at times overnight until around 6AM or 7AM. The heaviest snow will fall east of Route 495, but all areas will see snow.
On the radar image below I have put a rectangle around the area of precipitation moving northward overnight. It's this big area which will bring several hours of heavy snow to the region, especially within 30 miles or so of the coastline.
Topsfield has already picked up 15 inches, Rowley 16 inches of snow and other areas have seen near a foot. If these locations get another 8 or 10 overnight, they will easily close in on 20 to 24 inches of total accumulation.
While there has been some unpredictable and amazing snow totals thus far, most of the area has seen 3-7 inches. I have augmented the accumulation map to move the area of heaviest snow further into Essex and parts of Middlesex Counties. Itís impossible to tell you exactly how much snow you will see, because these bands are like summertime thunderstorms. If your house in under one of the bands, you are going to be at the high end of the snow total or even exceed the prediction by a bit.
When the storm is over, I believe this will end up being a memorable storm for parts of eastern Massachusetts, but just a typical snowstorm for most of the state. It will be interesting to see where these bands start forming overnight and how long different areas stay under the most intense bands. My highest predicted totals will be the exception, not the rule.
Snow bands can form and reform over the same area. Notice on the image below there are areas of heavy snow (green) and lighter snow (blue) just a few miles from one another. We can forecast that bands will form, but not the accurate placement of them.
Iíll be tweeting radar images showing where the bands are and where they are expected to move. When you view a radar image, look for the green areas, those will be places with the heavy snow of 1 or 2 inches per hour. This image shows the heaviest snow running southwest from Boston.
Travel isn't recommended the rest of the night and through 7AM Friday. After 7AM the heaviest of the snow will be winding down and improvement to roads will take place. It's going to take all day to clear some side streets in those areas that end up with the highest totals.
When will you update again?
I will give regular frequent updates throughout the storm. I update often on Twitter @growingwisdom. Feel free to chat with me there.
How about the wind and power outages?
The wind will be blustery and reach gusts over 35 miles per hour, mostly along the coast. These speeds alone are not enough to cause power issues. Because the snow will be so light, it's not going to stick to the wires, so I am not concerned about the power. Of course, there is always the possibility in any storm of isolated power outages.
How about the coastal flooding threat?
Each high tide cycle from now through Friday at noon is astronomically a high tide. This means the tides are higher than normal anyway, even without a storm. The maps below show the areas most vulnerable to minor to moderate flooding during this storm. These are predictive maps and are subject to change. The actual height of the water will be different when it occurs, but this gives coastal residents a good idea of what to expect.
How will air travel be affected by the nor'easter?
Airports are clearly greatly affected by the snow. Logan Airport has suspended travel from 8PM this evening until Noon Friday. How the storm unfold overnight will determine if that noontime start does happen.
When will the storm end?
The heaviest snow will exit the area between 5AM and 8AM. The progression of the back edge of the snow will mark steadily eastward so by 10AM any leftover snow should be over in Boston and by noon or 1PM the last of the snow should be exiting Cape Cod. The image below is for 8AM and give you an idea of where the heavy snow, light snow and back edge will be during that hour.
Will the kids have school Friday?
Many schools in eastern Massachusetts and Rhode Island have announced closures for Friday. Check your local area to see what the status of your school system is for Friday.
How cold will it be during the storm?
Temperatures are going to become very cold tonight and Friday. Temperatures will continue to slowly fall much of the rest of the evening and will be bitter cold by sunrise Friday. If you have issues with pipes freezing in cold weather you should do whatever you normally do to prevent that from occurring. If you leave your water dripping slowly, the movement of the water won't allow it to freeze. It's worth the money considering the alternative.
The wind is going to make it feel even colder than the actual temperature readings. Some towns will see wind chills reach 20 below and there could be a wind chill advisory issued for the cold. This is dangerous cold, I don't use that adjective often, but this cold is not something we see every winter.
Overall how bad will this storm be?
In many ways this is a classic storm, but everyone has different criteria for how they judge these storms. The over foot of snow before the core of the storm even has really started is noteworthy. Overall, this will be a typical January nor'easter. The blizzard warning makes it more serious for those driving tonight in those areas. The long duration will make it difficult if you don't like driving in snow, because there will be so many hours of snow on the roads. The length of time it will take the snow to occur and the light weight will make it easy to clear. The lack of widespread moderate or major coastal flooding won't make this storm memorable for coastal folks. I think one of the more notable aspects of the storm will be how much snow falls at such cold temperatures. It's not often we see significant snow with temperatures so cold, I am really interested to see just how dry the snow actually is especially at the end of the storm, when it's the coldest.